A study elucidating the synthesis and structure of the tegumentary free-surface membrane in cestodes is proposed. The surface of cestodes is implicated in integration of the parasite's physiology with the environment provided by the host via a selective nutrient assimilation function. Previous research has demonstrated a polyanionic carbohydrate or glycocalyx superficial to but as an intregal portion of the external plasmalemma. Because of their position and charge these glycoproteins are believed to control the quality of the microenvironment immediately adjacent to the membrane surface and consequently the activity of membrane bound enzymes. As evidenced in my own work, the synthetic origin of the surface membrane and its glycocalyx is within the tegument. The primary goal of the proposed research is to define the interrelationship of protein synthesis and subsequent carbohydrate additions during membrane synthesis employing specific inhibitors of synthetic and energetic pathways. Using the complementary techniques of high resolution autoradiography and biochemical methods on tissue and isolated membranes it will become possible to identify the intracellular levels and the molecular quality of inhibition. Differentiation of helminth membrane synthetic systems from those previously characterized in mammals may provide an insight into specific chemotherapeutic treatment of pathogenic helminths.